A farmer spraying crops near Thurstonland in Holme Valley,
West Yorkshire. Photograph: Ian Dagnall/Alamy
May 13, 2015
Glyphosate, the world’s most widely used herbicide, hit the
headlines in March after the International
Agency for Research on Cancer (IARC) announced that it is a “probable human
carcinogen”.
The IARC, which is responsible for providing an evidence
base for the cancer control policies of the World Health Organisation and its
members, had completed a year long review of the scientific literature on the
herbicide. It found “convincing evidence” that glyphosate causes cancer in
laboratory animals, “limited evidence” that it does so in agricultural workers,
and evidence that it causes DNA and chromosomal damage in human cells.
The IARC’s evaluation is hugely important because it is
sharply at odds with the views of the world’s major regulatory agencies. Last
year, an
evaluation by German government regulators, on behalf of the European
Commission, concluded that there was no evidence that glyphosate is
carcinogenic or mutagenic, or that the herbicide posed any other serious hazard
to health. All other regulatory agencies have reached similar conclusions.
The IARC did not have access to new evidence. So why has it
reached totally different conclusions about the hazards posed by glyphosate?
First, this kind of disagreement is not unprecedented, or
entirely surprising. Evidence about chemical safety is often incomplete,
uncertain and ambiguous, such that assessments of safety cannot always be
resolved on the basis of evidence alone. What, for example, constitutes a
reliable and relevant study? How should conflicting evidence be weighed? How
much of what kinds of evidence are necessary to support a judgement about
hazard, or its absence? Subjective judgements and assumptions, as well as
evidence, are typically required to settle such questions, so it is no wonder
that institutions sometimes disagree.
We do not know exactly why institutional evaluations of
glyphosate differed so markedly in this case because the IARC has yet to
publish its full evaluation (that is promised for later in the year). But, from
the IARC’s summary,
it appears likely that it used different criteria for choosing which evidence
to evaluate; made different judgements about the reliability of some of the
evidence; and interpreted the results of some of the experimental studies in
different ways.
Most regulatory agencies are reluctant to acknowledge that
there are choice-laden aspects to chemical safety assessment. This is partly
because science is a powerful source of legitimacy, and regulators often want
to portray their assessments as far more objective, reliable and consensual
than is actually the case. But it is also because to do so would be an open
invitation to scrutinise regulators’ technical assessments. We might reasonably
want to ask how have the choice-laden aspects of those assessments been
exercised: in ways that resolve ambiguities and uncertainties in favour of
public health, or in favour of agribusiness?
The IARC’s evaluation presents a dilemma for regulatory
institutions. If they explicitly accept the validity of the IARC’s findings
(and therefore acknowledge the choice-laden nature of safety evaluation) this
might invite scrutiny and criticism of their own assessments, and regulatory
decisions. The only alternative is to insist that the IARC’s review is
scientifically flawed or politically biased.
This latter tactic has often been adopted when individual
scientists criticize a sensitive regulatory consensus, but the IARC is a rather
formidable dissenter. It is about as scientifically rigorous
and independent an institution as they come. Its evaluations are conducted
by senior academic and regulatory scientists, drawn from around the world, and
subject to a strict conflict of interest policy.
IARC insists that its
evaluations are transparent and so all evidence used to support its evaluations
must be publicly available. The evaluation process is guided by published
scientific principles and assessment criteria, and is explained in considerable
detail in IARC’s monographs.
We don’t yet know how regulators will handle this dilemma,
but the agrochemical industry’s strategy is already clear: “[IARCs] result was
reached by selective ‘cherry picking’ of data and is a clear example of
agenda-driven bias” was Monsanto’s
reported response. The American Council on Science and Health, an
industry-funded “consumer” organization, opined
in similar style: “… [IARC] started out with the conclusion they aimed at
reaching, and then they evaluated the data they wanted to utilize to get to that
conclusion and ignored or manipulated the rest.”
This strategy is curious because it is bound to invite
comparison between the IARC and those regulatory institutions that have
supposedly produced a more impartial evaluation of glyphosate. And such comparisons
are unlikely to be favourable.
Readers might be astonished, for example, to learn that much
of the German government’s recent evaluation of glyphosate - favourably
compared to the IARC’s evaluation by the agrochemical industry - was not
actually written by scientists working for the German Federal Institute for
Risk Assessment (BfR), but rather by the European Glyphosate Task Force, a
consortium of agrochemical firms.
BfR
officials explained that due to the quantity of evidence they did not have
the time to prepare the toxicological evaluation themselves. So the
agrochemical industry wrote the descriptions, and evaluated the reliability of
each piece of evidence. These are exactly the kinds of choice-laden decisions
described earlier. BfR regulators commented, in italics, on the industry text,
but this falls well short of what most people would understand as an independent
review.
We do not know if the BfR evaluation is unusual in having
been drafted by the firms whose products were being evaluated, or unusual
because German regulators were honest enough to make that practice explicit.
But if one of the world’s wealthiest nations does not have sufficient resources
to conduct its own independent evaluations of toxicological evidence we might
well ask what are the practices in regulatory institutions elsewhere?
Source: http://www.theguardian.com
Of course the reality is that the pesticide and herbicide
companies will find a hired gun, an “expert” of their choice to write and say
whatever they wanted him/her to say.
This is the sad situation. The
federal and state agencies are stuffed with not very competent people and they
only respond to actual injurious incidents.
The people are pretty much helpless to the introduction of
new chemicals. And it takes many-many
years to realize the danger of these chemicals. Already we are faced with significant reduction
of the bee population (42 percent drop compared to 2013). Most of the produce is tasteless and
fake-looking. Meanwhile, the diseases
continue to take a toll on the population, especially asthma, contact dermatitis,
and so on.
This is the United States of Chemicals, the product of many
decades of chemical introduction and lack of regulation. Remember the PCBs, the DDT, the chlordane,
the asbestos, the silica sand, and so on?
Their environmental and health damage took many years to assess and
their effect is still lasting.